Fastener feed system

ABSTRACT

A rivet feed system which includes a base feeder assembly (28), having a rivet passageway (30) extending lengthwise therethrough. The base feeder assembly (28) includes cutout regions to receive rivet injectors (24) which are moved in operation between a first position and a second position. In the first position, an opening (80) in the injectors (24) forms a part of the passageway (30) through the base feeder assembly (28), while in the second position, the opening (80) is positioned directly beneath a vertically oriented rivet cartridge (22) to receive a rivet therefrom. The passageway (30) is connected to a source of pressurized air (32) which moves rivets therealong to a rivet machine or the like. The plurality of cartridges (22) positioned along the base feeder assembly contain rivets of various selected sizes. The rivet cartridges (22) are filled off line by means of a vibrating bowl feeder (117) and a rivet insertion assembly which includes a rivet pump (120) which automatically and repetitively moves rivets which have been inserted thereinto from the bowl feeder (117) into the rivet cartridge (22).

This is a divisional of application Ser. No. 027,834, filed on Mar. 8,1993, now U.S. Pat. No. 5,339,598, which in turn was a divisional ofapplication Ser. No. 693,628, filed on Apr. 30, 1991, now U.S. Pat. No.5,193,717.

TECHNICAL FIELD

This invention relates to an apparatus for supplying fasteners, such asrivets, to a tool, such as an automatic riveting machine, for use inassembly operations.

BACKGROUND OF THE INVENTION

All tools which use fasteners, such as rivets or the like, for variousfastening operations, such as in the manufacture of aircraft, require afastener feed system. Depending upon the tool, such a fastener feedsystem can be manual or it can involve various combinations andarrangements of mechanical and/or electro-mechanical assemblies which inone form or another automatically feed fasteners to the tool. In onespecific example involving rivets, an apparatus known as a vibratorybowl is used to supply rivets to a high production riveting machine.With the vibratory bowl, a large number of fasteners is emptied into thebowl, with the fasteners being randomly distributed. The combined effectof the configuration of the vibratory bowl and the vibrating actionresults in the rivets being positioned end-to-end in single file at theoutlet of the bowl. From the bowl, rivets are fed into an escapementline which in turn connects to a main rivet feed line to which a sourceof pressurized air is connected. The air moves the rivet at high speedin the main feed line, typically one at a time, to the riveting machine.

However, vibratory bowls have a number of disadvantages. One significantdisadvantage is their size and weight. Since each size rivet requires aseparate vibratory bowl, and since as many as thirty (30) differentrivet configurations are necessary in a large scale assembly operation,thirty (30) bowls would be required for such a rivet feeding system.This requires a considerable amount of space relatively close to theriveting machine.

In addition, while vibratory bowls are generally reliable, in operation,they do from time to time have jamming problems, particularly where therivets move from the bowl into the escapement line. In a completeassembly system using high speed automatic riveting equipment, all ofthe individual subsystems must be reliable for the overall system toperform well. While the use of vibratory bowls has had a negative effecton overall system reliability, there has been few if any viablealternatives to date with the vibratory bowl arrangement.

Hence, there is a significant need for a more reliable and morestreamlined system for automatically feeding fasteners to a fasteningtool such as a riveting machine.

DISCLOSURE OF THE INVENTION

Accordingly, the present invention includes a fastener feed system foruse with a fastener installation tool, comprising a base feeder assemblywhich includes a passageway therein for receiving fasteners and movingthose fasteners to a fastener installation tool; means for moving thefasteners along the passageway by fluid pressure, such as air; means forstoring the fasteners; and means for receiving a fastener from thefastener storage means and for injecting the fasteners into the fastenerpassageway. The receiving and injecting means is movable between firstand second positions. The receiving and injecting means includes anopening which forms part of the fastener passageway when it is in itsfirst position and into which a fastener is received from the fastenerstorage means when it is in its second position.

Also, the present invention includes a system for loading fasteners in acartridge, comprising means for supporting a cartridge which has aninternal opening for storing fasteners, the cartridge being adapted toreceive fasteners at a bottom end thereof, through an opening therein;fastener insertion means which includes means receiving fasteners meansfor moving a fastener into position beneath the bottom end of thecartridge and means for moving the fastener up into the cartridge; andmeans for feeding fasteners to the fastener insertion means in aselected orientation.

Still further, the present invention comprises a cartridge for storingfasteners from which fasteners are obtained and fed to a fastenerinstallation tool, comprising an elongated cartridge for storingfasteners from which fasteners are obtained and fed to a fastenerinstallation tool, comprising an elongated cartridge body, having aninternal opening which extends the length thereof, the opening havingdimensions slightly greater than the dimensions of the fastener; anopening at the lower end of the cartridge body for exit and entry offasteners; and a latch movable between a first position and a secondposition. In the first position the latch includes a portion thereofwhich extends over the opening at the bottom of the cartridge,preventing fasteners from moving through the opening and in the secondposition, the portion of the latch is moved relatively away from theopening, permitting fasteners to move therethrough.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of the rivet feed assembly of the presentinvention.

FIG. 2 is a cross-sectional view of the rivet feed assembly of FIG. 1,with the injection portion thereof shown in a second position.

FIG. 3 is a cross-sectional view of the rivet feed assembly of FIG. 1,with the injector portion thereof shown in a first position.

FIG. 4 is a cross-sectional view showing a portion of the rivet feedassembly of FIG. 1.

FIG. 5 is an isometric view showing a portion of a rivet cartridge.

FIG. 6 is an isometric view showing the rivet cartridge filling systemof the present invention.

FIGS. 7-9 are cross-sectional views of the rivet cartridge fillingsystem of FIG. 6, showing a portion of the system in various operatingposition.

FIG. 10 is an isometric view of a portion of the rivet cartridge fillingsystem of FIG. 6.

FIG. 11 is a side elevational view of the rivet cartridge filling systemof FIG. 6.

FIG. 12 is an isometric, partially exploded view of the rivet cartridgefilling system of FIG. 6.

FIGS. 13a-13c are simplified elevational view of an alternativeembodiment of a portion of the rivet feed system of FIG. 1.

FIGS. 14a-14c are simplified elevational view of another embodiment of aportion of the rivet feed system of FIG. 1.

BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 1 shows an isometric view of a portion of the fastener feed systemof the present invention, referred to generally at 20. While thefollowing description of the present invention is specific to rivetfasteners, for ease of explanation and illustration, it should beunderstood that the invention can be used for other similar fasteners.

Basically, the rivet feed system 20 includes a plurality of verticallymounted rivet cartridges 22--22, each cartridge containing a largenumber of rivets of a particular size arranged in a single column. Theactual number of cartridges 22--22 used in a particular rivet feedsystem will depend upon the number of different size rivets required forthe particular operation being performed by the riveting apparatus. Forinstance, if the riveting operation involves the assembly of an aircraftwing, a substantial number of cartridges will be necessary, while otherassembly operations may require a smaller number of cartridges.

Each cartridge 22 in the embodiment shown is mounted vertically on itsown horizontal injector mechanism 24 by means of a mounting latch system26. The cartridge 22 could be mounted in different orientations. Theinjectors 24--24 associated with successive cartridges 22--22 form partof a base feeder assembly shown generally at 28. Extending lengthwisethrough the entire base feeder assembly is a rivet passageway 30. Rivetsare driven along the rivet passageway 30 by pneumatic means shownrepresentationally by a source of pressurized air 32, actuated by asolenoid valve 34 which in turn is controlled by the system controlcircuitry (not shown). It should be understood, however, that actuationmeans other than pressurized air may be conveniently used.

As explained in more detail below, the rivet passageway 30 extendsthrough each of the injectors 24 when the injectors are in a firstoperating position, such that the complete passageway 30 is formed by afluid tight successive arrangement of injectors 24 in their respectivefirst operating positions and fixed intermediate portions of anotherpart of the base feeder assembly. In operation, the injectors 24 shuttlelaterally of the base feeder assembly 28 between their first positionand a second position where the opening in the injector which forms partof passageway 30 when the injector is in its first position, is directlybeneath its associated rivet cartridge 22. When the injector is in itssecond position, the lowermost rivet in the cartridge drops into theopening in the injector. The injector is then moved back to its firstposition, the source of pressurized air is actuated and the rivet isthen moved under high air pressure along the passage way to the rivetingmachine.

FIGS. 1-3, 5&12 show a rivet cartridge in more detail. The cartridge 22is elongated with a central opening or slot 36 which receives andretains a stack of horizontally oriented cylindrical rivets. The rivetsabut along their cylindrical surfaces in the embodiment shown, but theycould also be stacked end to end. The opening 36 is slightly larger thanthe dimensions of the rivet, in order to provide the rivets a minimumamount of freedom of movement, so that they might move downwardlyrelatively freely without becoming misarranged. In the embodiment shownthere is approximately a total of 15/1000ths clearance around therivets. In one embodiment, the cartridge 22 is formed by a shallowu-shaped back element 38 and a flat front element 40 which is attachedby means of screws 41--41 or the like to the free edges of the backelement 38. In one embodiment, the back element is metal, such asaluminum, and the front element is clear plexiglass, so that the numberof rivets in the cartridge may be readily ascertained by visualinspection. The cartridge 22 has an opening 42 at the bottom thereof tofacilitate entry and exit of rivets into and from the cartridge.

Near the lower end 43 of the cartridge 22, and extending forwardly fromthe front element 40 is a mounting element 44. The mounting element 44in the embodiment shown externals for the width of the cartridge, isapproximately two inches high and extends forwardly of the cartridgeapproximately 1/2 inch. In the upper part of the mounting element 44 isa cutout region 45 (FIG. 12) at the rear of the mounting element, thecutout region extending for the entire width of the mounting element,leaving an approximately 0.2 inch thick lip 46 at the front of themounting element and a space of 0.3 inch between the lip 46 and thefront element 40 of the cartridge. The lip 46 includes a centrallylocated notch 47. The notch 47 is approximately 0.5 inch deep, 0.3 inchwide and extends completely through lip 46. The cutout region, the lipand the notch are arranged to facilitate the insertion and removal of amounting latch, as explained in more detail below.

The cartridge 22 also includes a rivet catch shown generally at 50. Therivet catch 50 is a relatively thin but stiff metal member which ismounted to the rear surface of the back element 38, approximately 5inches up from the lower end thereof, by means of screws 51 or the like.The catch 50 extends downwardly therefrom until very near the lower endof the cartridge. Two side ear portions 52--52 of the rivet catch extendaround the cartridge 22, adjacent the respective sides thereof, to nearthe front surface 53 of mounting element 44. The side ears 52 include afront edge portion 56 which is generally parallel to the front surfaceof the mounting element 44, when the catch is in its forward (rest)position, and an angled edge portion 57 which angles upwardly from thefront edge portion 56 rearwardly to the remainder of the catch 50. Catch50 also includes a bottom ear 58 (FIG. 5) which extends around thebottom of cartridge 22 and across the rivet opening 42.

The entire catch 50 may be moved a small distance rearwardly of thecartridge about its mounting screws. When the catch is in its forwardposition, the bottom ear 58 extends across a substantial portion of therivet opening 42, thereby preventing rivets from entering or exiting thecartridge 22. However, when the catch 50 is moved rearwardly, such aswhen the cartridge is inserted into the base feeder assembly and themounting latch 26 is operated, bottom ear 58 moves sufficiently awayfrom the rivet opening 42 so as to permit entry and exit of rivets. Thecartridge 22 is both filled and emptied through opening 42.

A steel follower plate 62 is positioned in the opening 36 in thecartridge, on top of the rivet stack therein. The steel follower plate62 is free to move with the downward movement of the rivets within theopening as the rivets exit from the cartridge and prevents the rivets inthe stack from vibrating to a skewed orientation during operation of therivet feed system. A magnet 64 is positioned near the lower end of thecartridge 22, accessible to the internal opening 36. The magnet 64captures the follower plate 62 when all the rivets have exited thecartridge, thereby preventing follower plate 62 from falling through therivet opening 42. Alternatively, the follower plate could be a piece ofmaterial, such as lead, with a magnet in it. The magnet 64 has no effecton aluminum rivets.

The base feeder assembly 28 is shown in detail in FIGS. 2-4. The basefeeder assembly 28 includes a plurality of injectors 24, each uniquelyassociated with a particular cartridge 22, as explained above, arrangedin sequence along a feeder line, as shown in FIG. 4. Referring to FIGS.1-3, the feeder base assembly also includes a lower base plate 70 whichextends the entire length of assembly 28 and which in one embodiment is60 inches wide by 13/4 inches high. Positioned on top of the lower baseplate 70 is an intermediate base element 72 which also extends thelength of the base feeder assembly 28. The forward vertical edge 74 ofintermediate base element 72 is an extension (vertically) of the forwardvertical edge 76 of lower base plate 70. Intermediate base element 72overlies a substantial portion of lower base plate 70, extendingrearwardly from their respective front edges 76 and 74. At successiveintervals along the length of the intermediate base element 72 arecutout regions to accommodate successive injectors. Each cutout regionextends from the rear edge 78 of the intermediate base element 72, andextends forwardly approximately 7 inches and is 2 inches wide. Theintermediate base element is approximately 0.25 inches thick over thearea of the respective cutout regions. Into the cutout regions arepositioned the rectangular injector elements 24--24. Each injectorelement 24 in the embodiment shown is approximately 41/2 inches long, 2inches wide and 1/4 inch high. The side edges of the injector elementmate with the sides of the cutout region in the intermediate baseelement 72. In the embodiment shown, there is approximately 5/1000thsbetween each side of the injector and the intermediate base element, inorder to maintain a fluid-tight relationship. In the top surface of theinjector is a longitudinal opening 80. The opening 80 in each injectorforms a portion of the overall rivet passageway 30 which extends thelength of the base feeder assembly.

Positioned on the upper surface 82 of lower base plate 70 toward therear edge 81 thereof are successive air cylinder elements 84, therespective extending arms 86 of each of which are connected to rear ofsuccessive injectors 24. In operation, the air cylinder 84 moves theinjector 24 between two positions. In a first or rest position, theinjector 24 is in its most forward position, abutting the intermediatevertical edge 79 of the intermediate base element 72 as shown in FIG. 3.When the injector 24 is moved to its second position by the aircylinder, opening 80 in the injector is positioned directly beneath theopening 42 in the rivet cartridge, permitting a rivet from the cartridgeto fall into the opening 80, as shown in FIG. 2. The injector is thenmoved back to its first or rest position. Pressurized air then is usedto move the rivet along the complete passageway 30 formed by openings 80in successive injectors and alternating openings in the intermediatebase element 72 which are in registry with the openings 80 when theinjectors are in their first positions. Overlaying the top of theintermediate base element 72 and a portion of the successive cutoutregions and hence openings 80--80 when the injectors are in their firstposition, is an upper base plate 88. The upper base plate 88 extends thelength of the base feeder assembly.

Mounted on top of the upper base plate 88 and associated with eachsuccessive cartridge 22 are a plurality of hold down clamps 26--26. Eachhold down clamp 26 includes aim upstanding base member 92 which ismounted directly to upper base plate 88. The base member comprises twospaced apart L shaped flanges in the embodiment shown. Pivotally securedto the base member 92 are two spaced apart arms 94 and 96 which extendupwardly from the base member 92 and then come together in combinationwith a cap 97 to form a handle 98. Extending from each base member 92,in particular from between the two L shaped flanges thereof toward itsassociated cartridge is a t-shaped member 100. Pivotally connectedbetween the two arms 94, 96 and the t-shaped member 100 is a shortlinking member 102. The two arms 94, 96, the t-shaped member 100 and thelinking member 102 are arranged so that as handle 98 is moved away fromthe cartridge, the t-shaped member 100 rotates away from the cartridgeto a vertical position, while when the handle is rotated toward thecartridge, to a vertical position, the t-shaped member 100 moves to ahorizontal position in which the elongated leg portion 104 of thet-shaped member fits into the notch 47 of the mounting element and thetop cross bar portion 106 fits snugly just behind the lip 46 of themounting element, thereby holding the cartridge firmly in place on thebase feeder assembly.

In operation, cartridges with rivets are positioned along the base feedassembly as needed, with each cartridge having a different size rivettherein. All of the injectors are positioned in their first position,thereby defining a continuous fluid tight passageway along the basefeeder assembly. Connected to the base feeder assembly is a source ofpressurized fluid, such as air. Individual rivets are then movedsuccessively into the passageway by operation of the injectors, moving,by means of the air cylinders, from their first position into theirsecond position to receive a rivet and then back into their firstposition, with the rivet now in the rivet passageway. The solenoid valveconnecting the source of pressurized air to the passageway is activated,and the rivet is moved through the passageway to the tool, for use inassembling a selected product such as an aircraft wing or the like.

FIGS. 13a-13c show another embodiment for the rivet injectors. In thisembodiment, the rivets 103 are stacked end-to-end in the cartridge. Theinjectors 105 rotate 90° from a first position, shown in FIG. 13a, to asecond position, shown in FIG. 13b, to receive a rivet. The injectorthen rotates back to its first position, as shown in FIG. 13c; the rivetis now in the passageway 107, along which it is moved to the tool.

FIGS. 14a-14c show another embodiment involving a rotating injector 113.In a first position, as shown in FIG. 14a, a longitudinal opening 115 inthe injector 113 forms part of the extended rivet passageway. Theinjector is rotated 90° to a second position, where it receives a rivetfrom the cartridge, as shown in FIG. 14b. The injector is then movedback into its first position, as shown in FIG. 14c, with the rivet nowin the passageway.

FIGS. 6 through 12 show another aspect of the present invention, inparticular a system for filling the cartridges with rivets. Thecartridge filler system shown generally at 109 includes a rivet pumphousing 110, at the top of which is a mounting plate 112 having a cutoutportion therein 114 which mates with the configuration of the lower endof a cartridge 22. On plate 112 is mounted a hold down clamp 26 which isidentical in structure and operation to the hold down clamps 26 usedwith the base feeder assembly. The purpose of hold down clamp 26 is tohold the cartridge 22 in a vertical orientation for filling, althoughthe cartridge could be filled in the other orientations. The rivetfilling system includes a conventional bowl feeder partially shown at117 in FIG. 6. The rivets from bowl feeder 117 are lined up end-to-endand fed into a rivet pump assembly contained in housing 110. The rivetpump assembly is shown in FIGS. 7 through 10. The rivets aresuccessively correctly initially positioned in the rivet pump assembly120 by a proximity sensor 122, which is positioned in one side of thehousing 110. The proximity sensor 122 is mounted in an assembly 123which permits adjustment of the position of sensor 122 to accommodaterivets of various lengths.

The rivet pump assembly 120 includes a double action rod-like cylinder124 which extends out the side of the case 112. Mounted on the cylinder124 are two identically configured cam elements 126 and 128. The camelements 126 and 128 are approximately 1/8 inch thick, generallycircular in outline, approximately 2 inches in diameter and are fixablyconnected to the cylinder approximately 3/8 inch apart. The two camelements 126 and 128 include identical scooped out portions 130. Scoopedout portion 130 is defined by a surface which includes a leading edge133 which extends from the peripheral edge 134 of the cam elementinwardly thereof approximately 1/4 inch, where it begins to curveoutwardly into a flat portion approximately at right angles to theleading edge 133, and then curves gently to blend into the peripheraledge 134. The scooped out portion 133 covers a radial distance of 90°.

Positioned between the first and second cam elements 126 and 128 is athird cam element 142 which rotates freely around cylinder 124 betweenthe cam elements 126 and 128. Cam element 142 is approximately 1/4 inchthick and has the same diameter as first and second cam elements 126 and128. Positioned at 90° intervals around the peripheral edge of camelement 142 are four notch-like portions 144a-144d, which are configuredto receive a rivet. In operation, referring to FIGS. 7 through 9, one ofthe notches 144a in cam element 142 is lined up with the forward part ofthe respective scooped out portions 130 of cam elements 126 and 128,which are in registry as indicated above. A rivet is moved into thenotch 144a, from the bowl feeder, so that it extends laterally acrossthe three cam elements, below the peripheral edges of the cam elements.This is the first step in the rivet filling process and is illustratedin FIG. 7. The proximity sensor determines the correct initial axialposition for the rivet.

The cylinder 124 is then rotated approximately 95°, carrying with it thefirst and second cam elements 126 and 128, as well as cam element 142and the rivet, since the rivet in effect joins all three cam elementstogether for rotation when the cylinder is rotated in the directionshown in FIG. 7. After slightly more than 90° of rotation, the notch144b, which is 90° removed from the notch containing the rivet, comesinto mating contact with a pivoting pawl 146. The top end 148 of pawl146 enters notch 144b, as shown in FIG. 8. At this point, notch 144a andthe rivet therein are directly beneath the rivet opening in the lowerend of the cartridge; the rotation of cylinder 124 is stopped. Thecylinder 124 is then rotated in the opposite direction, as shown inFIGS. 8 and 9, taking with it the first and second cam elements 126 and128 back to their original rotational position. However, the third cam142 remains in place, because of the restraining action of the pawl 146.As the two cam elements 126 and 128 rotate, the rivet rides on thesurface of the scooped out portions thereof, and as the surface comescloser to the peripheral edge of the first and second cam elements, therivet is forced upwardly into the cartridge, as shown partially in FIG.9. When the cylinder 124 moves to its original position, it is now linedup with notch 144d in the third cam element, and the apparatus is set toreceive the next rivet from the vibrating bowl. The rotation of thecylinder 124 in both rotational directions is provided by an aircylinder 149, positioned on the side of housing 110.

This process continues until the cartridge is completely filled. Whenthe rivet stack nears the top of the cartridge, a proximity switch 60,which is located in a housing which supports the upper end of thecartridge during rivet filling operations, senses the approachingtopmost rivet (or follower plate 62) and terminates the action of therivet pump. The filled cartridge is removed from the mounting plate 112and is stored for future use with the base feeder assembly, as describedabove.

In summary, rivets are initially placed in a vibratory bowl feeder, andthen moved one by one into the rivet pump, which fills a givencartridge. The filling of the cartridges is done "off line" from therivet feed system. The filled cartridges are stored, ready to be usedwhen needed in the rivet feed system. The rivet feed system includes abase feeder assembly which includes injectors which move rivets from therivet cartridges which are now mounted on the base feeder assembly intoa rivet passageway and then to the riveting tool. Although a preferredembodiment of the invention has been disclosed herein for purposes ofillustration, it should be understood that various changes,modifications, and substitutions may be incorporated in such embodimentwithout departing from the spirit of the invention as defined by theclaims which follow:

What is claimed is:
 1. A cartridge for storing fasteners from whichfasteners are obtained and fed to a fastener installation tool,comprising:an elongated cartridge body, having an internal opening whichextends along the length thereof, the opening having dimensions slightlygreater than the dimensions of the fastener; an opening at the lower endof the cartridge body for exit and entry of fasteners; and a latchconnected to the cartridge body and having a bias action tending to movethe latch to a first position relative to the cartridge body, the latchbeing movable between the first position and a second position, whereinin the first position, the latch includes a portion thereof whichextends over the opening at the bottom of the cartridge, preventingfasteners from moving through the opening and wherein, when the latch isforced away from the first position against the bias to the secondposition, the portion of the latch is moved relatively away from theopening, permitting fasteners to move therethrough.
 2. A cartridge ofclaim 1, including a mounting element located near the bottom of thecartridge, adapted to cooperate with a clamp for the cartridge mountedsuch that when the clamp is holding the cartridge in place, a portion ofthe clamp moves against the latch, forcing the latch from its firstposition to its second position.
 3. A cartridge of claim 1, includingmeans for maintaining the relative orientation of the fasteners duringentry and exit of fasteners from the cartridge.
 4. A cartridge of claim1, including a magnet positioned at the lower end of the cartridgeadjacent the internal opening and a follower element which rides on topof the uppermost fastener in the cartridge, moving downwardly as thefasteners move from the cartridge means, maintaining time fasteners inproper relationship, wherein the magnet captures the follower elementwhen the follower element comes into proximity with the magnet,preventing the follower element from moving through the opening at thelower end of the cartridge.